Obese Couples Risk Lower Fertility

Weight Loss Reduced Time to Conception continued...

Obese women had a 78% greater risk of being sub-fertile than normal-weight
women, and obese men had a 49% increased risk for sub-fertility than
normal-weight men.

The risk of taking more than a year to achieve a pregnancy was 2.74 times
higher when both partners were obese than for a normal-weight couple.

The researchers further examined 2,374 couples who had more than one
pregnancy. When they converted the length of time that it took the women to get
pregnant into days, they concluded that for overweight or obese women, every
2.2 pounds of weight loss reduced the time to conception by an average of 5.5
days.

Heavier Men Have Less Sex

The suggestion that weight loss seems to improve fertility for both women
and, to a lesser extent, men has important potential public health
implications, says epidemiologist Donna Baird, PhD, of the National Institute
of Environmental Health Sciences (NIEHS).

Baird co-authored a 2006 NIEHS study that linked obesity to infertility in
men. The researchers concluded that a 3-unit increase in BMI increased the risk
of infertility by about 10%.

At least one other study has linked obesity in men to a decline in sperm
quality, but Baird says more research is needed to confirm the association
between body weight and infertility in men.

She adds that the decline in fertility among overweight and obese men may
have more to do with sexual function than sperm quality.

“There are a lot of gaps in what we know,” she tells WebMD. “We didn’t have
data on the frequency of sexual intercourse among men, and we know that obesity
can certainly impact sexual function. Low libido and erectile dysfunction, for
example, are much more common in obese men.”